Dual language correction in OS X

Ok, so I'm a postgrad historian who studies the Spanish Inquisition. I am constantly quoting in Spanish, etc. Is it possible to have my mac set for English AND Spanish. By which I mean to say it will correct both languages? If so, how?

Good news! Yes there is! And this is how:

Go to System Preferences -> International -> Input Menus -> Select any number of additional languages -> Keyboard shortcuts -> select the shortcuts you want to switch between languages -> back arrow -> check "Show input menu in menu bar" -> close system preferences.

Now go into a word editor and test your new languages! Its especially fun to type in Japanese

Hope this helps!

Ok, well I did that and I set my hotkeys, with Spanish as my preferred one and English just below it on the preference list. It isn't working though, even when I hit the hot key and I saw the little US flag at the top, it's still wanting to do spellcheck for Spanish... what am I doing wrong?